Stereoscope



Jan. 30, 1945. R E MCCLURE STEREOSCOPE Filed Nov. 7, 1941 3 Sheets-Sheet l Jan. 30, 1945.

R. E. MCCLURE sTEREoscoPE Filed NOV. 7, 1.941

3 Sheets-Sheet 2 Jan. 30, 1945. R. E. MccLURE STEREOSCOPE Filed Nov. 7, 1941 l 3 Sheets-Sheet 3 Patented Jan. 30, 19.45

UNITED STATES z PATENT ori-'ICE mh., Robert E. McClure. Ohio Application November 7,-(4-vS-e2rgl No. 418,203

1s My invention relates to stereoscopes adapted for 'viewing pairsrof stereoscopic pictures.I and.

encies, preferably the 21A" x 2%"size. v

Manufacturers of articles in colori particularly more particularly stereoscopic color ltranspar;V .v

for use in homes, such as colored wall and ilooiI coverings including wall paper, paint, rugs, carpet, linoleum, tile, and the like, and such as curtains, drapes, furniture, and ornaments, and such as dinnerware, enameled kitchenware, and dining and kitchen utensils, and articles such as white enameled kitchen cabinets, sinks, stoves, and refrigerators, usually used in conjunction with colored wall and floor coverings, curtains, drapes, furniture, and ornaments, have a difficult problem in showing in three dimensional form the articles in their various color combinations to prospective purchasers.

Numerous attempts have been made 'to provide stereoscopes for this purpose, but such stereoscopes have either been only suited for the relatively small 35 millimeter color transparencies which are not of satisfactory size when viewed directly, or have been relatively complicated` and expensive to make, precluding their use in large numbers.-

thanwhen made of heavier metal ness andstrength.

v The objects of the present invention include the provision-of an improved stereoscope and the like,

particularly adapted for 'direct viewing of 2%" x 2%" stereographic color transparency slides, using daylight as a source of illumination when daylight is available in suitable intensity.

The 21/4" `i: 21/4" stereographic" color transv leither by daylight, or by artificial light.

- From another standpoint in a stereoscope adapted for mass production, it is desirable to make the parts as much as possible from nonmetallic sheet material such as paper, cardboard, cellular paper boxboard, and .the like, which is lighter and easier to work than metallic sheet material of the same thickness necessary to give the desired stillness and strength to the parts.

In use, a stereoscope including parts most of which are made of non-metallic sheet material,

such as paper, cardboard, cellular paper boxboard, and the like, is light as well as stift and strong, and it is easier for a salesman to carry Further objects of the present invention include the provision of such an improved stereoscope with aremovable source of artificial light.

Eurther'objects of the present invention include the provision of such an improved stereo-4 clude the provision of an improved stereoscope of simplified construction and arrangement, and adapted for easy and economical manufacture and maintenance, regardless of the material of which it is made. i

, The foregoing and other objects are attained by the stereoscopes, constructions, parts, combinations, and sub-combinations comprising the present invention, the nature of which is set forth in the following general statement, preferred em bodiments of which are set forth in the following description, and which are particularly and distinctly pointed out and set forth in the appended claims forming parthereof.

The nature ofthe improved stereoscopecf the present invention may be stated in ygeneral terms as including an outer box sub-assembly,^an inner divider sub-assembly, and an inner lens mount sub-assembly, each sub-assembly including parts made from formed blanks of sheet material, preferably non-metallic sheet material such as paper, cardboard, cellular paper boxboard, and the like.

Each of the sub-assemblies may be quickly and conveniently made, and the sub-assemblies interflt and telescope with eachother to produce the complete stereoscope in a manner permitting very rapid and economical manufacture, and in such a way as to produce an easily operated and convenient stereoscope.

The improved stereoscope is particularly adapted for viewing stereographic color transparency slides,- and is provided in an improved manner with a light diffusing sheet at its admitting end.

The stereoscope may thus be used with daylight as a source of light whenever daylight is available and in suitable intensity.

When necessary however the improved stereoscope is provided with an improved removable source of artiilcial light, including a housing. adapted for telescoping on the light admitting end oi' the stereoscope and having operatively mounted therein vone or more electric lights.

By way of example, preferred embodiments of the improved stereoscope and parts thereof are illustrated in the accompanying drawings forming part hereof, in which Figure 1 is an isometric view of the improved stereoscope with a stereographic color transparency slide inserted, portions of the top `wall of the stereoscope outer box and other walls being shown in section and being cut away;

Fig. 1a, an isometric view of one of the stereographic color transparency slides for use with the improved stereoscope;

Fig. 2, an enlarged plan sectional view thereof with the slide removed, as on line 2 2, Fig. 3;

Fig. 3, a fragmentary longitudinal sectional view thereof, as on line 3 3, Fig. i2;

Fig. 3a, a view similar to Fig. 3, illustrating a modified embodiment of the improvedstereoscope;

Fig. 4, disassembled isometric views of the three subassembllespf the improved stereoscope;

Fig. 5, a plan view of a preferred form of blank for the box sub-assembly of the improved stereoscope; l

Fig. 6, a plan view of a blank for a diffusing sheet frame;

Fig. 7, a plan view of a diffusing sheet;

Fig. 8, a plan view of a blank for one of the two parts of the divider sub-assembly of the improved stereoscope; l

Fig. 9, a plan view of a blank 'for the lens mount sub-assembly for the improved stereoscope;

Fig. 10, a plan view of one of the mounts which may be used for making the stereographic color transparency slides particularly adapted for use with the improved stereoscope;

Fig. 1i, a view of an improved removable artificial light unit for the improved stereoscope showing a cover thereon;

Fig. 12, an enlarged isometric view of the light unit in its position ready for use, portions being broken away and shown in section; and

Fig. 13, a smaller view similar to Fig. l2 showing the improved light unit in use on the improved stereoscope.

Similar numerals refer to similar parts throughout the several views.

The improved stereoscope is indicated generally by I 0, and includes three sub-assemblies. an outer box sub-assembly Il. an inner dividerY subassembly I 2, and an inner lens mount sub-assemby I3, shown disassembled in Fig. 4.

Each of the sub-assemblies includes one or more blanks preferably made of light nonmetallic sheet material such as paper, cardboard. cellular paper boxboard, and the like.

One form of blank II-I for the box subfusing .transmitted light, auch as sanded Cellophane, or diiiusing glass, is shown in Fig. 7:

For the divider sub-assembly I2, a rectangular blank I2.I is shown in Fig. 8 and may be made of cardboard or heavy paper.

For the lens mount sub-assembly I3, a blank |3-.I is shown in/ Fig. 9, and may be made of cardboard or heavy paper.

For the stereographic transparency mount I4, particularly adapted for use with the stereoscope I0, a blank II---I isA shown in Fig. 10,'and may be made of cardboard or heavy paper.

Fold lines are indicated by dash lines inthe blanks II-i, I2-II and Il-I. l

The blank II-I includes from left to right as shown in Fig. 5, a box side wall I I--4a, a box assembly II is shown in Fig. 5 and is preferably bottom wall I|-5, a box side wall II-, a box top wall Ii-, and a box side wall II--4b.

From one end of the box bottom wall II-S extends a light di'using sheet frame II-8.

At the same end of the box top wall II-l extends a connector flap I I-9.

vThe side walls II-4a and iI-4b, are at the opposite ends of the blank II-l, and are rectangular, and the side wall II-4a is adapted for folding on the straight common side fold line II-IIl between adjacent sides of the walls II-da and II--5.

At the other side of the box bottom wall I I-5. parallel with the fold line II-lIl, there is 'a common side fold line lI-II between the box bottom wall II-5 and the box side wall II-G.

At the other side of the box side wall II-Ii,.

- and of the other three Walls of the tube formed from the blank. The similar ends of the outer blank Walls II-Ia and iI-Jh are II-I5a, and II-I5b, respectively. l

The bottom wall I I-B at one side of the shorter side wall II-6 has the rectangular diffusing sheet frame Il-8 extending from its similar end, with the end fold line I I-I6 between the diffusing sheet frame II- and the bottom wall At the other side of the shorterfside wall I I-6, the top wall I I'-'| has the connector ap II-9 e tending from its similar end, andthe end fold lne Il--Il is between the flap II--S andlthe top Wall II-'I.

After forming all the fold lines become bounding edges of their several walls, and the end fold lines II-IS and II--I1 are thus the ends respectively of the walls iI- and II-'|, and are alined with the outer wall ends II-I5a and II-I5b,

The oppositeends II-I8, II-I9a, and II--I9b of the walls II-6, II-la, and II-Ib, respectively, are alined with each other, whereas the similar end of the bottom wall II--S is a reversely concavelycurved end II-20 for accommodating the nose of the viewer, and the similar end of the top Wall II-1 is an arcuately curved end II-2I for accommodating the forehead of the viewer.

The blank I I-I, in conjunction with the light :,acacso dinusing sheet frame II--l which isI rectanguiar and matchesl the rectangular frame" II-I on the blank II-I,' and the lightv amusing-e.

sheet II-J, are utilized to make the outer box sub-assembly II, by folding the blank .I I-I on the several-fold lines and lapping theside wail I II4b over Vthe side wall IIe-4a, or vice versa,

opposite composite side wall including the overllapping walls II-la and II-4l The tube u has. e light admitting enc ls ma a vviewing end I8, and the frames II--l and the walls II-4a and II-Ib being the outer' walls `of the blank and being connected with each other as by gluing as is common in paper and cardboard box manufacturing, or by wire stapling, as maybe desired. L

The light diffusing sheet II`3 is lay'e`d prefere ably on the top of the frame II-l as shown on the plan view in Fig. 5, and the borders oi the light diffusing sheet 'II-l are secured as by gluing to the frame II-S, and preferably the frame blank II-2 is secured as by gluing on the other side of the light diffusing sheet II--3.

The frame II`8 with the light diffusing sheet II--l mounted thereon, after being swung up to the vertical position as shown in Figs. 3 and 4. `f is overlappedeby the connector flap II-s, the

outer border of the frame II-8 being connected.r

as by gluing with the connector flap II-9.

In the modified embodiment of the stereoscope indicated generally byl I Il' in Fig. 3a,j the, connector flap II-9 is eliminated on the top wall II-'I, and a connector flap II-S is provided,

on the end of the frame I'I-B, and is inserted beneath 'the top wall II-'I, the divider sub-` longer walls on each side thereof a notch be tween the adjacent longer walls for providing a stereographic transparency slide entrance II-23 in the finished sterecscope, as best shown in Fig. 2. f

The notch II23 is broadly a slide entrance formed in the side wall II-Il and for the mere purpose of an entrance might be a slot. j For other purposes of the invention, a slot entrance II-23 is provided by the notch and the adjacent edge IIe-24 of the assemblage of the frame II-a, the sheet II-3, andthe frame II2.

` The end portion II25 of the inner connector side wall II-4a opposite the entrance II--23 operates as a stop for the slides used in the im proved stereoscope.

The overlapping and connected side walls II-4a and II-Ib constitute a composite side wall in the completed stereoscope, and this composite side ,wall provides the slide stop II---25 opposite the slide entrance |I-23, regardless of which of the walls II-Ia and II-lb is inside.

Moreover, the inside wall might be cut away and the outer wall II-Ab would kthen provide the stop portion II-25, which would still be in the side wall of the box I I opposite the entrance l II-23.

IIJ-2 with the light diffusing sheet II-I secured therebetween, are atthe light admitting end Il of the tube Il.

.The blank I2-I i'or the divider sub-assembly I2 is rectangular and includes from left to right in Fig. 8, three rectangular walls I2-4, I2-l, and I2-I, the rectangular walls I2I and |2`4 having a fold line I2-B therebetween and the walls Il l and I2-5 having a fold line I2-'I therebetween, and the fold lines I2-8 and I2`I are parallel with each other and with the outer slides I2-Q and I2-9 oi' the rectangular blank I I.,

The ends ci the wens lz-s, Iz--s and n s In making the sub-assembly I2 a pair of the blanks I2-I are -folded on their fold ylines to constitute formed. pieces of sheet material each having walls on opposite sides offold lines, the formedpieces ,of'sheet material being deep channels in shape.

I n the complete divider sub-assembly I2, the 'base walls I.2-4 of each channel abut eachother and are secured to each other as by.. gluing.

These connected walls I2---4` constitute a composite "partition, which with the 'ange walls I2-3 and I2--5 of the back to back base ccnnected channels iitand telescope within the rectangular tube walls.

IThe' ends I2-I0 of the walls of the subassembly I2 are preferably unobstructingly alined with the entrance II-23, that is the ends I2 I0 are alined with the offset end' I I-Il of the box or top side wall II-G in the completed stereoscope as best shown in Fig. 2.

The common ends I2-I0 of the walls of the sub-assembly I2 alined withthe end II-Il of the box or tube side wall II-G form a guide for a sterographic transparency slide inserted through the entrance II-23.

Moreoverthe common ends I2-I0 of` the divider sub-assembly walls I2-3 and I2--5 form 'with theadjacent and opposite walls of `the frame II`2 upper and lower slide guidey grooves I'I, best shown in Figs. 2 and 3.

The blank I3--I for the lens mount vsubassembly I3, as shown in Fig. 9, includes a rectangular lens mount and closure wall I3--2 bounded by a bottom side I3-I0 of the blank I3--I, an opposite parallel fold line I3-I I, and opposite spaced end fold lines I3I2 and I3-I3.

At the outer side of the end fold line I3-I2 .extends a connector flap wall I3-I4, and at the outer side of the end fold line I3-I3 extends a connector flap wall I3-I5.

Beyond the side fold line I3-II preferably extends a. second lens mount closure wall I3-3. Each of the Walls I3-2 and lensapertures I3-I6 formed therein which are adapted to register with each other in making the completed sub-assembly I3 as shown in Fig. 4. The completed sub-assembly I3 includes a. lens I8 which is laid upon each aperture I3-I6 of the blank I3-I, and the lens mount closure wall [3 3 is folded over the feld une la-H endsecured as by gluing to the opposite face of the wall I3-2 mounting. the lenses I8 therebetween, one in each pair of registering apertures I3-I6.

The walls I3-I4 and I3-I5 are then folded in the same direction on the -fold lines `I3-I2 I3-3 has a pair of e 4 and I 2-Il to form the rectangular sub-assembly The sub-assembly I2 as made thus includes a formed piece of sheet material made from the blank .I2-I, and having walls on opposite sides of fold lines, and the sub-assembly I2 generally ment with the viewing end or the partition walls I2-4 of the sub-assembly` I2, and with the connector walls IS-Il and IS-IS secured to the'box ,or tube side walls.

. asse-,fasc I ,on the lightadmltting end 4Il ofthe stereoscope vided as shown a support and stop wall 21 which has a pair of apertures 2l therein serving as end supportsior the two elongated electric light bulbs i l 29 which constitute the electric light source 22.

as shown. The wall 2l extends from the preferably rectangular base wall SII of the housing 22 towards the sleeve 2l and terminates in the div rection of the sleeve 26 in a stop end 2l. -v For accommodating the slides Il, the housing `22,'which as shown is preferably rectangular.

y has a side wall l2 in which is yprovided a slide The partition formed by the abutting walls I2-4 thus extends longitudinally in the tube I I-,S and divides the same into side by side light compartments, the viewing end of which is provided with a closure by the lens mount and closure |3-2.

n the outside oi the lens mount and closure formed by the walls I1-2 and Il- S theinterior of the tube comprises a hood for obstructing light reaching the eyes of the viewer using the stereoscope III, except through the stereoseope. L For making a stereographic preferably color transparency slide Il for use with the stereoscope I0, a pair of stereoscope transparencies I9 are -glued or otherwise secured between the double frame mount blanks I4`l, each transparency being in the opening of one of the frames. Each mount Il-I as shown has a handle extension I42 by which the slide maybe grasped between the thumb and lingers o! the viewer. in handling the slide. .i

In using the stereoscope Il, with daylight of suitable intensity, a slide is inserted through the entrance II-23 until its stop end Il-I abuts against the stop portion II-25 of the side wall I I--Ia as shown in Fig. 1. The two stereographic transparencies I9 are then located at the viewing end of one of the light compartments within .the tube of the box II, opposite one oi.' the lenses Il,y which as shown is a iixed focus lens. The

of the stereoscope I B through the lenses I8 sees a three dimensional image, which when the ystereographic transparencies are 21/4" x 2%." is

very satisfactory in size for advertising Purposes.

When daylight of suitable intensity is not available the stereoscope Ill is preferably provided with an artificial light unit illustrated in Figs. 11', 12,l and 13, and indicated generally by 20, and which is generally rectangular in shape,l and which may havea rectangular cover indicated generally by 2i for protecting its interior when not in use. v

The details of construction of the light unit are best shown in Fig. 12, and the unit 22 preferably includes walls forming a housing indicated generally .by Y22 and having operatively slot entrance Il related to the stop end II, so

that when the light unit 20 has ,itsl sleeve por@ tion 2l telescoped over the light admitting end Il of the stereoscope III, as shown in Fig. 13, the

stop end s shuts against the .amusing sheet frame II-O and the light unit entrance 22 registers with the stereoscope entrance' II--2l.,

.The embodiments oi' the present improvements illustrated and described herein are by way o! example, and the scope of the present invention is not limited to the sameor to the ,particular details thereof, but is commensurate with any and all novel subject -matter contained herein which may at any time properly under the patent.

laws be set forth in the claims hereof or-originating herein, and the elements of any such claims are intended to include their functional or structural equivalents.

I claim: 1; In a stereoscope and the like. an outer box sub-assembly, an.`4 inner divider sub-assembly, and an inner lens mount sub-assembly; the outer box sub-assembly including walls forming a tube having a light admitting end and an opposite viewing end. a light diii'uslng sheet extending across and having borders secured to the tube adjacent the light admitting end, and the tube including -a sidef'wall having formed therein a stereographic transparency slide entrance adjacent the light diiusing sheet; the divider subd assembly including walls tting andv telescoping 1 within the tube walls and forming a partition extending longtiudinally in and dividing the'tube into side" by side longitudinally extending light compartments, the telescoping walls having ends sunobstructingly alined with the entrance and constituting a stereographic transparency slide guide: and the lens mount sub-assembly including walls forming a lens mount and closure extending across the tube in abutment with the end oi' the divider sub-assembly partition adjacent. `the viewing end of the tube, the lensv mount and closure having formed therein a pair of apertures, each aperture being at the viewing end of one of the light compartments, and a lens in each aperture.

2. In a lstereoscope and the like, as set forth in claim 1, and in which thcwalls are made of mountedwithin its interior an electric light source'indicated generally by 23 which may be powered as through a cable 2l and plug 25 vby connection o! the plug 25 with a suitable electric non-metallic sheet material, which is lighter and easier to work than metallic sheet material ,of the same thickness.

3. In a stereoscope and vthe like, an outer box sub-assembly, an inner divider sub-assembly,

and an inner lens mount sub-assembly; the outer l Within the housingA 22 there is preferably proasoaes'o transparency slide entrance notch adjacent the trame. and a light diilusing sheet having borders secured to the trame; the divider sub-assembly including a pair of formed pieces voi! sheet material each having walls 'on opposite sides ci told lines ntting and telescoping within the tube walls and including abutting walls forming a partition extending longitudinally in and dividing the tube into side by side longitudinally extending light compartments, the telescoping walls having ends unobstructingly alined with the entrance and constituting a stereographic transparency slide guide; and the lens mount` sub-assembly vincluding a formed piece of sheet material having walls on opposite sides of fold lines forming a lens mount and closure extending across the tube in abutment with the end of the divider sub-assemstereographic transparency slide entrance adjacent the light diilusing sheet; the divider -subassembly including walls forming a partition extending longitudinally in and dividing the tube into side by side longitudinally extending light lcompartments ,and forming a stereographic bly partition adjacent the viewing end of the tube and connector naps telescoping in the tube,- the lensamount and closure having formed therein a pair of apertures, each aperture being at the viewing end of one of the light compartments, and a lens in each aperture.

4. In a stereoscope'and the like, as set forth in claim 3, and in which the formed pieces of sheet material are non-metallic, and lighter and easier to work than metallic pieces of the same thickness.

e 5. In a sterescope and the like, an outer box sub-assembly, an irmer divider sub-assembly, and an inner lens mount sub-assembly; the outer box sub-assembly including a formed piece of sheet material havingwalls on oppositesides of fold lines forming a tube having a light admit-f ting end and an opposite viewing end andy a light diffusing sheet frame at the light admit-A ting end of the tube, and the tube'including a. side wall having formed therein a stereographic transparency slide entrance adjacent the iframe, and a light diffusing sheet having borders secured to the trame; the divider sub-assembly including a formed piece of sheet material having walls on oppositev sides 'of fold'lines tting and telescoping within the tube w'alls and including walls forming a partition extending longitudinalgitudinally extending compartments, the telescoping walls having ends unobstructingly alined with the entrance and constituting a stereographic transparency slide guide; `and the lens mount sub-assembly including` a' formed piece of sheet material having walls on opposite sides transparency slide guide unobstructinglv 'alined with the entrance.; and the lens .mount sub-assembly including walls forming a lens mount and closure extending across the tube and the end ot the divider sub-assembly partition adjacent the viewing end of the tube, the lens mount and closure having formed therein a pair oi apertures. each aperture being at the viewing end o! one of the light compartments, and a lens in each aperture.

8. In a stereoscope and the like, as set forth in claim 7, and in which the walls are made of non-metallic sheet material, which is lighter and easier to work than metallic sheet material of the same thickness.

Y 9. In a stereoscope and the like, a tube having a light admitting end and an opposite viewing end, a light difiusing sheet extending across and yhaving borders secured to the tube adjacent the light admitting end, and the tube including a side wall having `formed therein a stereographic transtube, a lens mount and closure extending across the viewing end of the light compartments, the lens mount and closure having formed therein a pair of apertures, each aperture being at the `ly in and dividing the tube into side by Side lon viewing end of one of the light compartments, and a lens in each aperture.

l0. In a stereoscope and the like, as set forth in claim 9, and in which the tube. the partition, and theI lens mount and closure, are made ot non-metallic sheet material, which is lighter vand -Y easier .to work than metallic sheet material of the same 1l. In a stereoscope and the like, a tube hav- I ing alight admitting end and an opposite viewing end, a transverse frame having borders secured to light admitting end portions of the tube.

. alight diilusing sheet extending across and havof fold lines forming a lens lmount and closure extending across the tube in abutment with the end of the divider sub-assembly partition adjacent the viewing.` end of the tube, and connector ila'ps telescoping in the tube. the lens mount and closure having formedl therein a pair of apertures, each aperture being at the viewing end ot one of the light compartments, and a lens in each aperture.

6. In` a stereoscope and the like, as set forth in claim 5, and in which Vthe formed pieces of sheet material are non-metallic, and lighter and easier to work than metallic pieces of the same thickness.

7. In a stereoscope and the'like, an outer box sub-assembly, an inner divider sub-assembly, and an inner lens mount sub-assembly; the outer box sub-assembly including walls forming a tube having a light admitting end and an opposite viewing end, a .iight diffusing sheet extending across and having borders secured to the tube ing borders secured to the frame, and the tube including a side wall having formed therein a stereographic transparency slide'entrance adjacent the frame and light diiusing sheet, a partition dividing the tube into side by side longitudinally extending light compartments terminating within the tube at one end in unobstructing relation with the entrance and at the other endadjacent the viewing end of the tube,

transverse walls spaced from the frame and forming therewith stereographic transparency slide grooves extending from the entrance, a lens mount and closure extending across the viewing end of the light compartments, the lens mount and closure having formed therein a pair of apertures, each aperture being at the viewing end of one of the light compartments, and a lens in each aperture.

12. In a stereoscope and the like, a tube having a light admitting end and an opposite viewing end, a transverse frame havingborders secured to the tube adjacent the light admitting end, and the tube including a side wall having formed therein a stereographic transparency.

side of the frame, a partition dividing the-tube into side by side longitudinally extending light compartments terminating` within the tube at one end in unobstructing relation with the entrance and at the other end adjacent the viewing end of the tube, transverse walls spaced from the frame and torming'therewith stereographic transparency slide grooves extending from the entrance, a lens mount and closure extending across the viewing end of the light compartments, the lens mount and closure having formed therein a pair ofapertures, each aperture being at the viewing end of one of the light compartments, and a lens in each aperture. y

13. In a stereoscope and the like, a tube having a light admitting end and an opposite viewing end, a transverse frame having borders secured to the tube adjacent the iight admitting end, a light diffusing sheet extending across and having borders secured to the frame, and the tube including a side wall having formed therein a stereographic transparency slide entrance one side of which is formed by one side of the frame, a partion dividing the tube into side by side longitudinally extending light compartments terminating within the tube at one end in unobstructing relation with the entrance and at the other end adjacent the viewing end of the tube, transverse walls spaced from the frame and forming therewith stereographic transparency slide I aseasso v walls ofthe tube and forming a notch between Athe adjacent longer walls for providing a stereographic transparency slide entrance, the longer tube wall opposite the notch forming a stop for the slide in the formed tube.

15.v In a stereoscope outer box sub-assembly and the like, ilve side by side walls having fold lines between adjacent walls, the side by side walls being folded on the fold lines and the outer walls being connected with each other to form a rectangular tube, one of the walls of the tube with two fold lines having an end inwardly offset from the similar ends of the other three walls of the tube and forming 9, notch between the adjacent longer walls for providing a stereographic transparency slide entrance, the longer tube wall opposite the notch forming a stop for the slide in the `formed tube, and one of the walls at one side of the notch extending beyond the ends of the notched wall and the stop wall and having an end fold line and a rectangular frame beyond andfolded on the end fold line.

16. In a stereoscope outer box sub-assembly and the like, iive side by side walls having fold lines between adjacent walls, the side by' side walls being folded on the fold lines and the outer walls being connected with each other to form a rectangular tube, one of the walls of the tube with grooves extending from -the entrance, a lens mount and closure extending across the viewing end of the light compartments, the lens mount and closure having formed therein a pair of apertures, each aperture being at the viewing end of two fold lines having an end inwardly offset from the similar ends of the other three walls of the tube and forming a notch between the adjacent longer walls for providing a stereographic transparency slide entrance, the longer tube wall opposite the notch forming a stop for the slide in the formed tube, and one of the walls at one side of the notch extending beyond the ends of the notched wall and the stop wall and having a first end fold line and a rectangular frame beyond and folded on the ilrst end fold line, and the other wall at the other side of the notch extending beyond the end of the notch wall and the stop wall and having a second end fold line and a connector flap beyond and folded on the second end fold line for securing with the frame.

ROBERTl E. MCCLURE. 

